Can't create a view based on first term

Using Drupal 5.10 and Views 5.x-1.6.

I create a new vocabulary V for Pages, then add say 3 terms to it, 'a', 'b', and 'c'.

I create a view and add a filter 'Taxonomy: Terms for V'. I see only terms 'b' and 'c' in the list of possible terms to filter on.

If I rename 'a' to 'z', then I only see 'b' and 'z' in the list. So the view seems to not be picking up the first term (alphabetically, not tid).

Work around: add a dummy term 'aaaa do not use'.

I have tried clearing the Views cache.